It has been customary for a front hood constituting the front of an automobile, when colliding with the head of a pedestrian, to deform to some extent and absorb impact load, thereby suppressing damage to the head of the pedestrian. In recent years, the Technical Standards for the Protection of Heads of Pedestrians, which define the impact reducing performance of the front hood, have been introduced. The front hood is required to fulfill these Standards. That is, it is required that the HIC (Head Injury Criteria) value of the front hood within a predetermined evaluation area be a predetermined value or lower.
In accordance with recent changes in the designing of automobiles, headlamp devices are showing a tendency to be upsized, and those having a surface shape continuous with the front hood are on the increase. That is, the surface of the headlamp device together with the front hood have substantially constituted the upper surface of the front of the automobile. Some of the headlamps, therefore, have needed to satisfy the Technical Standards for the Protection of Heads of Pedestrians as do the front hoods.
On the other hand, proposals have been made, for example, for a headlamp device composed of a headlamp housing having a shock-absorbing portion which has a sectional shape opening toward the rear of a vehicle, and which has a plurality of ribs provided inside (see Patent Document 1).
By structuring the headlamp device as above, an impact force exerted in a collision of an automobile with a pedestrian or the like is absorbed by the deformation of the shock-absorbing portion, and the impact force acting on the pedestrian can be mitigated.